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For deer hunting at longer ranges 300+ yards I don't think you can go wrong with the 7 and they carry it at the local hardware store or Walmart unlike a STW or Weatherby. You certainly don't need one for 140 lb. whitetail does at 85 yards.
But it isn't the hottest newest sexiest caliber like it was when I was a kid.
Like you I often recommend a .30-06 - to the point that a .30-06 is what I buy for wedding presents for sons-in-law. For Daughter #1 I recommended a .308 Win.
The problem with "deer hunting at longer ranges 300+ yards" is that you never know at what range you will actually be shooting. On one occasion I anticipated a 300 yards shot if I was lucky, 600 if not. Instead I had an opportunity at 25 feet.